Mechs Over the Traverse
by sage97
Summary: Ten years after the end of the Interstellar War, the Coalition of Democratic Extrasolar Colonies discovered something unusual on the outskirts of the Shanxi system: a massive alien artifact that proclaimed to humanity, "You are not alone." First Contact with different actors.
1. Chapter 1

I'm not exactly sure if this is required, but I'll still say it just in case. I don't own Mass Effect or Mecha Ace. The former is property of Bioware and the latter is the property of Paul Wang.

* * *

 **Orbit over Shanxi, Shanxi-Theta System**

 **429 Interstellar Era**

Rear Admiral Robert Kim gave a sigh as he leaned back into the smartfoam padding of his command chair. After the adrenaline-filled years of war he spent in the cockpit of a combat armature, peace-time in a dreadnought was almost boring. Not that that was a bad thing. After all, boring meant safety, the safety of his ship, his crew, and, above all, the safety of his family. But even though he spent the war fighting for this peace, he couldn't help but feel a slight sense of longing for his old Manningham Combat Armature.

On the other hand, with that _thing_ on his viewscreen, life wasn't as boring as it could be. It had been a month since his small fleet was assigned to guard both the object and the research teams assigned to study it. The massive construct was... graceful, a pair of arms nine miles long surrounding a pair of rings and a core of an unknown element which had the scientists going nuts for the past several weeks. But what worried the soldier was the simple fact that they knew nothing of it: who built it, its purpose, even what's it's made of. For all they knew, it was a massive weapon of mass destruction like the Lightbearer.

Which was the reason that, out of all of the fleets CoDEC had at its disposal, _his_ was the one assigned to protect the contruct. A motley collection of Interstellar War era vessels, the backbone of the fleet was his dreadnought and two Caliburn class carriers built after the war, along with their flights of Lionheart combat armatures. And, of course, the hero who ensured CoDEC's victory during the war happened to be its commanding officer.

Ten years, he had commanded the Temeraire and her battlegroup. Ten years since the Interstellar war had ended with CoDEC as the reigning power over every human colony. Ten years since the politicians started debated over changing the name of the state from the Coalition of Democratic Extrasolar Colonies as, with the conquest of Earth, CoDEC was no longer just a collection of colonies outside Sol. Though it was, thankfully, democratic.

Ten years of a hard-earned peace. And with the giant construct all but announcing to humanity that it was no longer alone in the universe, Admiral Kim prayed that the peace would last long past his lifetime.

But if it didn't, he was prepared to go to war again. He was prepared to risk life and limb to protect his people, his crew, and above all else, his family.

And he would make sure that _anyone_ foolish enough to start a war during his lifetime would live just long enough to regret it.

* * *

AN: One of my first fanfictions submitted to this site and it's a crossover. For those of you not familiar with Mecha Ace, it is a text adventure video game written by Paul Wang. Check it out at . Please review so that I can get better at writing.


	2. Chapter 2

**Relay 241, Qon'lok System**

 **2657 Galactic Standard**

Captain Ka'hairal Balak of the Batarian Expansion Forces leaned against his command console as he looked over his bridge. His was a small fleet, like all initial expeditionary forces. After all, the fewer ships sent, the lesser the cost for the Hegemony. But that only applied to ships that belonged to the Hegemony itself. His small fleet of 5 frigates led by his cruiser, Khar'shan's Blade, may be the only ships that the Hegemony sent, but they weren't alone. Accompanying them would be a fleet of pirates and slavers, all attracted by the first right to plunder anything that lay on the other side. This force would be enough to subjugate any species too primitive to use eezo tech. As it should be.

Of course, the fools on the Council would shrill loudly about the "moral injustice" of the entire affair, but their words lacked any substantial bite. After all, the more slaves the Hegemony could wring from primitive races, the fewer slaver raids the Hegemony would sponsor. Especially since the two most common slave races after lower caste Batarians were Asari and Salarian. After all, the Hanar were useless as were the Volus; the Drell too few; the Quarians were too high-maintenance; Turians fought too hard for a raid to be worth the investment; and the Elcor, well... the last group of slavers to hit an Elcor colony had to be washed off the pavement. Literally, with high-powered hoses and chemicals to wash away the blood.

Going back to the Council, though, there have been... disturbing rumors that those spineless pyjaks were considering expelling the Hegemony from Citadel Space. Already the Hegemony had been struck with numerous unfair sanctions over Batarian societal and cultural values. Yet the Hegemony still persevered, proof that, whatever the Council claimed, the Batarian way of life was a success. These rumors though, if they were true, simply served to show the hypocrisy of the Council who claimed to respect and value all cultures, yet looked down on the Batarians.

But the whining of politicians wasn't Balak's concern. Not now, anyway. No, what concerned him now was before him: Relay 241, and the possibly one-way-trip to explore the region around an dormant relay before activating it for the trip home.

Quietly, of course. There was still that little law against activating dormant relays. Of course, since the Attican Traverse was largely unexplored, it wasn't difficult to claim that a Relay had been "discovered" in an active state or that the relay had gone active in the absence of any observers. And, worst came to worst, the incident could be blamed on the Terminus. After all, noone can control or predict the actions of a Terminus warlord.

As the bridge techs finished the last preparations for Relay travel, faintly, he wondered if there was some power on the other side of the relay. A force, like the Rachni, which was better left alone. He banished the thought. Come what may, the Hegemony would overcome. The Hegemony would dominate.

As it should be.


	3. Chapter 3

**Orbit around Unknown Construct, Shanxi-Theta System**

 **429 Interstellar Era**

Admiral Kim looked around the bridge, making sure that no one was watching him before quickly stretching out, letting out a breath in relief as he felt his vertebrae pop several times. He inhaled deeply as he settled back into his seat, the rigid, upright angle of its back being the only thing keeping him from losing himself in the comfortable padding. Just another half-hour before the next duty shift which meant he could grab a quick bite before-

"Sir, Variable-Inertia Field detected!"

 _And there goes lunch._

Before he could take a breath, ships blue-shifted in-system next to the construct. By the time he exhaled, twenty new contacts had appeared on-screen, a good four hundred kilometers away from his battle group.

Fingers flew across his command terminal as he brought up the visual feed. The fleet that just appeared near the construct was a motley collection of vessels, even more so than his own. The five ships near the center of the formation, if the cluster of ships could be called that, were the only ones that seemed to share a standard design pattern. Likely military, or at least manufactured for military use, and thus they probably the most dangerous ships.

The rest reminded the admiral of pirates that still plagued the shipping lanes between colonies, or of the CoDEC fleet in the early years of the war, repurposed civilian ships and obsolete naval vessels. Effective, and often equipped with unpleasant surprises, but unable to stand against a sufficiently powerful force.

The familiar ache where the stump of his right hand interfaced with the prosthetic and the itch on the back of his left hand kept him on edge. His instincts, honed over five long years of brutal combat, hadn't been dulled by ten years of relative peace.

Admiral Kim took a moment breathe, before giving the order.

"General Quarters. All hands to action stations and put all ships on alert. I want Cobalt Lance in their armatures and ready to launch. Tactical, load ASCM tubes 33 through 64, warm up the point defense guns, and begin drafting firing solutions for the fleet." Alarms blared as the bridge crew rushed to complete their tasks, a picture of calm compared to the flurry of activity that surged through the rest of the ship.

"Do you think they will attack us, sir?" Ensign Maria Delgado, the ship's bridge controller. Like most of his crew, she had joined the navy after the Interstellar War and aside from the occasional pirate flotilla, hadn't seen much action. Unlike her contemporaries, she wasn't chomping at the bit to see combat, which made her among the more sensible ones in his book.

"I hope that they won't. But I'd rather be ready for an attack that won't come than be caught unprepared." But there was still a question to be answered: if they weren't hostile, how could they communicate? Radio was out. A civilization advanced enough to travel through the stars could certainly detect radio waves, but there was no guarantee that they could decipher them. And even if they could, there was no way that they'd understand the language. And they'd have no way to open, decode, or decompress a data packet of any kind.

Of course, there was the old science fiction stand-by of using some sort of mathematical sequence, Fibonacci or the sequence of prime numbers for example. Simple enough to accomplish, a clear attempt at intelligent communication, and unlikely to be misconstrued as an insult. Which left the question of which sequence to use.

The ship shuddered as alerts flared across consoles and damage reports flooded internal communications.

"Damage to armor in section 14, sir."

"The Laskey was just destroyed, sir!"

"Muzzle doors of ASCM tubes 15, 17, and 31 damaged; they won't open!"

"What are your orders, sir?"

 _Or they could remove the need for a means of communication with wanton violence._

"All ships, open fire. Launch all combat armature lances." He quickly marked down the five military vessels in the center as priority targets and sent the data to Ensign Delgado. "Inform the lance commanders that they should attempt to cripple these vessels if possible."

"Aye, sir." There was only a brief bit of hesitation before she responded and carried out her orders. Good. She has the sense to not ask questions during combat. Low thumps emanated from the deck as 11 megaton antimatter warheads launched from their tubes. Comm chatter increased as Saber, Iron, and Cobalt Lances launched from their carriers, the pilots exuberant and nervous at fighting an alien threat.

A few keystrokes brings the visual feed back up, the screen showing the hundreds of missiles streaking towards the alien ships, quickly followed by the fleet's combat armatures.

These aliens just made the mistake of attacking mankind.

He would ensure that they would regret even considering it.

* * *

Times like these, Balak regretted working with pirates. Some of the eyeless bastards had let their greed get the better of them and attacked without thought or provocation.

He had felt something was wrong when they first examined the alien ships. All of them projected mass effect fields, in the form of spheres of various sizes. Crude and inefficient, the sign of a technologically inferior species fit for servitude, if it wasn't for the lack of element zero.

They hadn't had the time to survey the whole system, but it was clear that the only element zero in the vicinity was in the mass relay. No trace eezo in their ships, not even a gram. And yet they could produce a mass effect field, with ships that large out this far which implied some form of FTL.

This was technological development on a level that even the Batarians hadn't managed, and the potential implications were lucrative at best and terrifying at worst. Regardless, this was a species with whom diplomatic relations might have been preferable to outright conquest. Oh, it would have led to their subjugation, but through a lighter touch, and with fewer Batarian casualites.

Now, they no longer had that option. All they could do is quickly subjugate them and pray that this system was the alien's home system.

The rhythmic thumps of the main cannon firing punctuated his thoughts as he watched hundreds of missiles approach his fleet on the tactical screen. And amidst the controlled chaos of his crew frantically bringing the GARDIAN system online, he made a remark to his first officer.

"Remind me to kill the bastard who fired first."

What a damn shame. These aliens might have been interesting.


	4. Chapter 4

**In combat near Unknown Construct, Shanxi-Theta System**

 **429 Interstellar Era**

The bridge of a starship in the middle of combat was nothing like how it's portrayed in the holovids. There are no zaps or other sound effects as weapons are fired. There are no consoles exploding, sending random nameless crewmen flying and in need of medical attention. There's no wild shaking unless the ship was about to be destroyed by its own VIFGs.

But there were minor tremors as the alien slugs slammed into the hull, fracturing the meters of armor. Low thumps echoed through the room as missiles left their tubes and accelerated towards the enemy. And there was the chattering of officers relaying orders to their subordinates, either on the bridge or into a vidfeed.

And through it all, the admiral sat there, seemingly impassive, the picture of professional composure amongst the organized chaos of the bridge's combat activities. Only the hard-set line of his jaw and the tightness of his grip on his chair's armrests gave away his concern as his eyes stared at the tactical display.

It had only taken a few seconds to realize that, against this foe, the standard deployment of frigates ahead of their cruisers, battlecarriers, and dreadnought had been a mistake. It took two minutes to rectify that, and in that time, five of their eight frigates had fallen to the combined firepower of the alien fleet, the remaining three having taken refuge behind the larger superstructures of the CoDEC capital ships.

Still, they had given even better than they got. The order of the day had been rapid fire as the alien's offensive strength was proven. The veritable storm of missiles, hundreds, if not thousands, of antimatter warheads had completely overwhelmed their point defense systems while simultaneously boxing them in, making it impossible to dodge one missile without hitting another. When the first salvo passed, only six of the original twenty vessels remained, all of them scorched from warheads destroyed only a few kilometers from their hulls.

Of course, with Cobalt, Saber, and Iron Lances so close to the enemy, it was impossible to let loose another salvo, lest the run the risk of friendly fire. So, as his ship's weapons crews rushed to reload the empty magazines with fresh ACSMs, he gave the order.

"Cease fire."

It was up to the pilots now.

* * *

Balak's hands shook against his command console as he looked over the results of the past five minutes of combat. His eyes twitched at the inconceivability, the audacity, of these aliens as he tried to shove aside the fear and helpless rage that welled up in him so that he could assess the situation.

Two minutes. For two minutes, Balak's fleet had savaged the aliens. Their lack of eezo tech translated to a lack of kinetic barriers and mass drivers, leaving them vulnerable and unable to effectively retaliate, or so they thought. Mass driver rounds punched through their ship's hulls, or tore away armor plating with glancing blows. Five of their frigates were destroyed, all of them crumpling in on themselves and imploding after their mass effect generators were hit. The remaining three frigates took refuge behind the cruisers and dreadnoughts. But even the heavier ships were badly damaged, venting atmosphere through gaping holes.

And then the missiles had arrived. Hundreds of them, their numbers quickly rising into the thousands as the aliens filled the space between their fleets with flying explosives, sped towards the pirates and Batarians. They had the first hint that something was wrong when their mass driver rounds disappeared upon striking them, the brilliant flash vaporizing the slugs.

The threat was apparent. His cruiser brought its broadside guns to bear and let loose. Every ship in the fleet warmed up their GARDIAN arrays. And when those missiles reached GARDIAN range, they were in for a worse surprise as the absurd amount of radiation released by every destroyed warhead fried kinetic barriers, scorched the hull, and threw off the sensors.

It was the last effect that was the most dangerous. Each explosion disrupted the sensors for only a split second, but when there were hundreds of simultaneous disruptions screwing with the targeting VIs of the GARDIANs, that severely degraded their performance.

The result?

Only six ships remained, including the Khar'shan's Blade. Three of them were Blood Pack, the Krogans having armored them absurdly so that ramming was a viable tactic. One of them was a slaver vessel that had sat in the rear, having escaped unscathed by a serendipity of deployment. The last was Balak's last remaining frigate under his command, the Adek Warhawk.

The survivor's responses were mixed, to say the least. The Krogan, being Krogan, decided to charge in a suicidal rush. The slaver vessel, Balak forgot the name, was clogging up the comms channels by broadcasting a mix of distress signals and an offer of surrender to the aliens. The Warhawk remained the picture of Batarian naval discipline, its captain sending a single message requesting orders and a recommendation that they withdraw from the system.

For the first time in his career, Balak seriously considered it. This was an enemy that had cut them down from a numerical advantage to a severe disadvantage. An enemy that threw what could only be Type III Weapons of Mass Destruction around like an inexperienced slave trainer administered whippings. An enemy that they had just pissed off.

The Hegemony needed to be warned.

He had no idea what their FTL capabilities were, but he would take no chances. This new species was something the Batarians hadn't encountered since they met the Turians: a powerful space-faring race that challenged the Batarian's rightful place as the galaxy's master race.

This could not be tolerated.

It would not be tolerated.

He took a deep breath.

"Retreat. Turn the ship around and prepare to jump to Relay 241."

He had sealed his fate.

He was now a failure in the eyes of the Hegemony, a crime for which he would die.

As both the Blade and the Warhawk started to turn prepared to transition to FTL, he hoped that the information he was bringing back would spare his family and the Batarians.

* * *

Lieutenant Kazim Asadi had mixed feelings about this engagement. On one hand, they had destroyed fourteen ships at the cost of five of their own. On the other hand, they had lost five ships to an unknown enemy.

And unfortunately, the ACSMs, while an effective weapon, didn't leave much behind besides wreckage. Which meant that disabling the alien vessels for capture and study fell to the mecha corps.

The commander of Cobalt Lance looked at the feed from his main external camera. Three of the enemy vessels were charging at the fleet, looking to the universe like they were planning on ramming the Temmeraire. That was going to be a problem.

The sole unscathed vessel was maintaining its position, broadcasting some alien signal. He hoped it was some sort of surrender. But, better safe than sorry.

And the two surviving HVTs were turning tail, probably retreating.

That was unacceptable.

He was the seniormost pilot on the field, which meant that, theoretically, he had the authority to give orders to the other lances.

Time to put that authority to the test.

He opened comm lines to Saber Lead and Iron Lead, their faces appearing on screen.

"Saber Lead, what is it?"

"This is Iron Lead, go ahead."

"Iron Lead, I need you to take your lance and stop those three ships before they ram the flagship. Saber Lead, have your lance secure the lone vessel. Cobalt Lance will handle the HVTs. Understood?"

The commander of Saber Lance opened his mouth in a grimace, frustration showing on his face as it grew red. Iron Lead, on the other hand, mulled over his orders before nodding.

"Acknowledged. Iron Lead out."

The tactical display showed Iron Lance breaking off to intercept the charging ships as his vidfeed winked out. Saber Lead fumed for a moment longer before letting out a breath.

"Fine. We'll do it."

Asadi let out the breath he had been holding as the comm channel closed and Saber Lance broke off to secure the stationary vessel.

Now all he had to deal with were the two military vessels.

Both of them had turned around and were accelerating towards the alien structure. However, the way that they came into the system proved they had some sort of FTL system.

They could jump at any time.

It was imperative that at least one of those ships be captured intact if possible. But letting either go was unacceptable. Not after what they did.

The faces of his lancemates came onscreen as he contacted the unit.

"Saber Two, take Three and Four and hit the frigate. Five and Six, we're after the flagship. Remember, disable them if you can, destroy them if you can't. Copy?"

A chorus of acknowledgements rang out. Saber Two, however, had one last thing to say.

"Good hunting, boss."

Asadi smiled.

"Good hunting, Anderson."

 _And then there were three_ , he thought as Anderson's detachment left to attack the frigate. He brought his combat armature's particle storm rifle to bear, the giant mecha shouldering the rifle as it hurtled towards the enemy.

"Particle rifles up. Aim for the engines. Once she's adrift, knock out her weapons and drag her to a halt."

"Got it, boss-man."

"Yes, sir."

He nodded. "Good. Stay sharp. We have contact in... five."

He made one last check on his particle rifle, keeping an eye on the counter. The links to the his power plant were green, and the cooling system was working well within acceptable parameters.

"Four."

His eyes darted once more to the tactical screen. Saber Lance was rocketing towards the surrendering vessel. Poor bastards were probably freaked out. Iron Lance had already engaged the enemy, doing their best to slow them down.

"Three."

He closed his eyes for a second, taking in a deep breath. He felt the combat drugs rushing through his system, heightening his awareness and his reaction times. He felt the straps holding him to his seat, and the weightlessness from the lack of acceleration. He took care to not think about the tightness of his pilot's suit, which clung to his body like a second skin. It was comfortable, until he thought about it.

"Two."

He opened his eyes as he let the breath out. His thoughts turned to his older sister, Fatima, now a full Commander in command of Phoenix Lance. She hadn't approved of her baby brother following in her footsteps. If she knew what he was doing, fighting on the front lines against an alien foe, would she be proud of him? Or would she be worried? Knowing her, probably both.

"One."

He banished the thoughts of his sister. No more distractions. His heart pounded in his ears as his eyes focused on the targeting system, the timer counting down until the engine he was aiming at was in range. His index finger rested on the trigger.

"Contact."

A feral grin grew on his face as he squeezed the trigger.

* * *

Author's Note:

Holy crap, a new chapter in a little over a month. A bit of a rush job, but knowing me, it was either this or mulling over every detail for the next 8 months. So, yeah. Please review and help me improve.


End file.
